"The airlines have consistently been losing money . . . They (the airlines) are just trying to test that point (at which customers don't buy tickets) and see where it is," Stempler said.

Kerosene-based jet fuel prices in the New York harbor area rose from more than $1.48 per gallon in May 2005 to about $2.14 this May, according to the
U.S. Energy Information Administration
, a federal agency.

According to the EIA's latest forecast, jet fuel prices - tied closely to crude oil - should remain stable for the rest of the year, falling mostly between $2.01 and $2.05 per gallon.

"Airline fuel prices are going to be pretty high for a while," said
Neil Gamson
, an economist and fuel price forecaster for the EIA.